RO76748B1

RO76748B1 - Process for stabilizing microcapsule aqueous suspensions

Info

Publication number: RO76748B1
Application number: RO101034A
Authority: RO
Inventors: Demetra Dragan; Doina Mihai; Adrian Carpov
Original assignee: Institutul De Chimie Macromoleculara "Petru Poni"
Priority date: 1980-05-05
Filing date: 1980-05-05
Publication date: 1983-02-28
Also published as: RO76748A2

Abstract

Inventia se refera la un procedeu de stabilizare a unor suspensii apoase de microcapsule, în care, în scopul evitarii fenomenelor de separare de faze prin semidentare, ecremare, aglomerare, la durate mari de stocare se trateaza o suspensie apoasa de microcapsule continînd un insecticid organo-fosforic ales dintre fosforoditionat de 0,0-dietil-S-2-(etiltio)-etilsi fosforotiolotionat de S-(1,2-di-(etoxicarbonil)-etil)-dimetil, microcapsule avînd pereti de poliuree sau de poliuretan-poliuree reticulati, obtinuti prin poliaditie interfaciala a unor di si poliizocianati aromatici sau a unor aductii de toluilendiizocianat si trimetil olpropan cu polialchilenpoliamine, dimensiuni cuprinse între 1 si 100 niu un continut de material polimeric în perete de 2....15% densitati ale miezului cuprinse între 0,98 si 1,2 g/m suspensiile apoase de microcapsule avand un continut în substanta activa de 8....30 g/100 ml de suspensie si valori ale pH-ului de 8...10 cu un amestec omogen constituit din xantan si clorura de sodiu sub forma de pulbere solida, în concentratie de 0,1....0,3% xantan si 0,1....1% clorura de sodiu raportat la greutatea solutiei apoase, în timp de 2....5 min, direct în vasul de sinteza a microcapsulelor, sub agitare timp de 1/2....1h, la o turatie de 250....350 rot/min si apoi timp de înca 1/2...1 h la o turatie de 100.....150rot/min, operatiile avand loc la temperaturi cuprinse între 20 si 40 degree C.The invention relates to a process for stabilizing aqueous microcapsule suspensions in which, in order to avoid phase separation phenomena by semicantration, erection, agglomeration, at high storage times, an aqueous suspension of microcapsules containing an organo- phosphoric acid selected from S- (1,2-di- (ethoxycarbonyl) -ethyl) -dimethyl-0,0-diethyl-S-2- (ethylthio) ethyl phosphorothionate and polycrystalline or polyurethane- crosslinked, obtained by interfacial polyaddition of di and polyisocyanates or of adducts of toluylene diisocyanate and trimethylolpropane with polyalkylene polyamines, sizes between 1 and 100 niu, a polymeric material content in the wall of 2 ... 15% of core densities between 0.98 and 1.2 g / m aqueous microcapsule suspensions having an active substance content of 8 ... 30 g / 100 ml of suspension and pH values of 8 ... 10 with a homogeneous mixture constituted di n xanthan and sodium chloride as a solid powder in a concentration of 0.1 ... 0.3% xanthan and 0.1 ... 1% sodium chloride based on the weight of the aqueous solution over 2 .... 5 min, directly into the microcapsule synthesis vessel, with shaking for 1/2 ... 1h, at a speed of 250 ... 350 rpm and then for an additional 1/2. .1 h at a speed of 100 ... 150 rpm, operations taking place at temperatures between 20 and 40 degrees C.